SEATTLE -- NaVorro Bowman held onto that ball.

The 49ers' best defensive player ripped it from Seattle receiver Jermaine Kearse and, though his left knee was violently dislodged from normalcy, he finished the play and got the offense the ball back.

The officials missed the call and robbed him of the fumble recovery. But it didn't rob the 49ers defense of its heart, which Bowman had exhibited all season, even on his final, gruesome play.

San Francisco's defense was not as dominant as it needed to be Sunday. The 49ers gave up 20 points in the second half. They failed to contain Marshawn Lynch, who beasted for 109 yards and a score. They gave up more than 200 yards and the game-winning touchdown to a passing game no one outside of Seattle deems potent.

But when things looked most bleak, when the Super Bowl rested on its shoulders, the defense came through. The defense got the ball back to the offense with a chance to win. Twice. Even without the unit's best player.

It was such display of resilience, defensive coordinator Vic Fangio went to each player and told him he loved them.

"I kissed most of them. I don't think I've ever done that before," Fangio said, later adding, "They're a bunch of fighters we've got here. They're class guys. Great players. Great individuals. Great football character. It doesn't surprise me."

It's a fitting end to the season. That side of the ball has bent all season but refused to break. The toughness and fight that has come to be known as 49ers football is because of that side of the ball.

Ultimately, San Francisco's defense wasn't good enough to make it back to the Super Bowl. Not to overcome the big plays they gave up. Especially not to overcome the offense's mediocrity this day.

Seahawks quarterback Russell Wilson, who was running for his life much of the first half, scrambled his way into a rhythm in the second half. That opened up the 49ers defense enough for Lynch to rumble for a 40-yard game-tying score in the third quarter.

Then, early in the fourth quarter, the 49ers did what they hadn't done this postseason: give up the go-ahead score in the second half. On fourth-and-7, Kearse beat 49ers cornerback Carlos Rogers, hauling a perfect pass from Wilson for a 35-yard touchdown. The 49ers trailed 20-17.

Five plays into the ensuing series, Kaepernick was sacked and fumbled away the ball, sending the struggling defense back onto the field.

The season was over, it appeared. Seattle, which had been getting just about whatever it wanted on offense, had the ball first-and-goal, six yards away from turning the game into another slaughter.

But the 49ers defense wasn't about to fold. That mentality was symbolized by Bowman, who made a play when San Francisco needed it the most.

"He's a great player. He's the leader," nose tackle Glenn Dorsey said. "It was unfortunate he got hurt on that play. You've got to just keep on going. Keep on fighting."

The ruling on the field was that Bowman caused the fumble but Lynch recovered. The replay showed Bowman clutching the ball on his back, his left leg pointing in a direction that makes you squeamish.

Despite the raw deal, the very next play after losing Bowman, the defense held on fourth-and-1 as Wilson fumbled the handoff. The 49ers were still alive.

Two plays later, the defense was back on the field, backs pressed against the wall again by Kaepernick's interception. But the defense mustered another critical stop, holding the Seahawks to a field goal. The 49ers had the ball with more than three minutes left, needing a touchdown to win it.

"We always say just play to the end," Rogers said. "You never put your head down. Just go out and play. ... We were in that mode of playing football, trying to get stops, trying to get them the ball back."

This unit won't play together again. Cornerback Tarell Brown and safety Donte Whitner are free agents. Just judging by the sheer look of his injury, Bowman could miss most or all of next season.

San Francisco's defense could use some upgrades -- in the talent, depth and scheme department. Certainly to reach Seattle's level.

But before the curtain closed on the season, the 49ers defense made one last stand. Actually, two. It was the kind of heart you hope marks this side of the ball for years to come.

Contact Marcus Thompson II at mthomps2@bayareanewsgroup.com. Follow him on Twitter at twitter.com/ThompsonScribe.